I'd appreciate if you could help.
I recently find out that the user especially smartphone user using POP3 for sending and receiving message. they reported that they cannot send email to external recipient without VPN or outside company network, e.g. at home.
I tried using Outlook Express or MS Outlook 2003, it is true that the message can ONLY send to internal recipient. Unless my smtp account is set to SMTP server given by my local ISP, then I can send to external and internal recipient. I went for business trip recently, I find out that I cannot send email in and out, I change SMTP server to my Exchange Server's public IP. I can only send to internal recipient but not external. So I called for that country ISP, change my SMTP server settings again, it works for in and out.
I start to realize that it is very inconvenience to cause that I have to know their own smtp servers of different ISP.
I would be good if SMTP account authenticated successfully through my Exchange Server 2003, it can be send in and out to internal and external recipient. So that, I won't require to know other SMTP server.
Anyone encounter? Any solution for me?